1.A state of being acquainted, or of having intimate, or more than slight or superficial, knowledge; personal knowledge gained by intercourse short of that of friendship or intimacy; as, I know the man; but have no acquaintance with him.

Contract no friendship, or even acquaintance, with a guileful man.
Sir W. Jones.

2.A person or persons with whom one is acquainted.

Montgomery was an old acquaintance of Ferguson.
Macaulay.

&hand; In this sense the collective term acquaintance was formerly both singular and plural, but it is now commonly singular, and has the regular plural acquaintances.
To be of acquaintance, to be intimate. -- To take acquaintance of or with, to make the acquaintance of. [Obs.]Syn. -- Familiarity; intimacy; fellowship; knowledge. -- Acquaintance, Familiarity, Intimacy. These words mark different degrees of closeness in social intercourse. Acquaintance arises from occasional intercourse; as, our acquaintance has been a brief one. We can speak of a slight or an intimate acquaintance. Familiarity is the result of continued acquaintance. It springs from persons being frequently together, so as to wear off all restraint and reserve; as, the familiarity of old companions. Intimacy is the result of close connection, and the freest interchange of thought; as, the intimacy of established friendship.

Our admiration of a famous man lessens upon our nearer acquaintance with him.
Addison.

We contract at last such a familiarity with them as makes it difficult and irksome for us to call off our minds.
Atterbury.

It is in our power to confine our friendships and intimacies to men of virtue.
Rogers.